ᐅ Costs of a Geothermal Borehole – Is It Worth It in Our Case?

Created on: 1 Dec 2017 14:02
A
arnonyme
Hello,

I have received a quote for a geothermal drilling. About €21,000 for 260 drilling meters (2 x 130 m (430 feet), water protection area, so the use of antifreeze is not possible), heating load around 8 kW.
Can someone tell me how this quote compares price-wise?
Or whether it is even worth pursuing geothermal energy further?
It seems quite expensive to me, especially when I read that some have paid only €6,000.

Best regards and thanks
Steffen
bluminger2 Dec 2017 21:06
Different funding criteria apply for existing buildings and new constructions. Therefore, many (or perhaps all?) air-to-water heat pumps that would be eligible for funding in existing buildings are not eligible for new constructions.

It would be very interesting if you or someone else manages to achieve this for new builds as well.
R
ruppsn
2 Dec 2017 21:44
Good point, I wasn’t aware of that at all. However, the offers from HLB explicitly mentioned the eligibility for funding in new construction. I will double-check that again once it becomes relevant. For now, I’m hoping that the excavation will start on Monday... [emoji51]
But thanks again for the tip!
A
Alex85
3 Dec 2017 06:23
Being listed in the table is a good start, but in my opinion, the annual performance factor must still be verified after one year. However, that can be looked up.
bluminger3 Dec 2017 08:50
In new buildings, an annual performance factor of 4.5 must be achieved. Anyone can check this for their system using the annual performance factor calculator.
T
Tentakel
4 Dec 2017 09:01
According to our heating engineer, it is not possible to receive subsidies for a single-family home with an air-to-water heat pump, even with good systems. I also did some calculations online, and in southern Germany it is definitely not feasible. In the north, it might be possible because different outdoor temperatures are allowed to be assumed there.

Try calculating the savings from the drilling against the additional costs. New air-to-water heat pumps still operate at -20°C ( -4°F), but then only with a COP of 1.8 to 2.

For us, the drilling would pay off at the earliest after 25 years.
R
ruppsn
4 Dec 2017 09:13
From a purely economic perspective, you can generally do without a ground-source heat pump, unless the additional cost is only a few thousand euros. Once it reaches five figures, the calculation usually doesn't add up anymore.

But it's not just about heating. “Cooling” in the summer, aesthetic reasons (no equipment in the front yard), and environmental considerations can also play a role.

From a purely payback perspective, an air-to-water heat pump is definitely advantageous.

Thanks for the tip about eligibility for subsidies; I really thought that was a given [emoji6]